Chilkat2-Python

Get a Certificate's Key Size

See more Certificates Examples

Demonstrates how to get the RSA key size of a certificate (for example, 1024-bit, 2048-bit, etc.) Chilkat2-Python

import sys
import chilkat2

success = False

# For this example, I have a certificate in raw base64 format (not PEM),
# that looks like this:  "MIIGkDCCBHigAwIBAgIUMDA ... s/iqLsLA=="
sbCertBase64 = chilkat2.StringBuilder()
success = sbCertBase64.LoadFile("qa_data/certs/base64Cert.txt","utf-8")

cert = chilkat2.Cert()
success = cert.LoadFromBase64(sbCertBase64.GetAsString())
if (success == False):
    print(cert.LastErrorText)
    sys.exit()

# Get the public key.
pubKey = chilkat2.PublicKey()
cert.GetPublicKey(pubKey)

numBits = pubKey.KeySize
print("Number of bits = " + str(numBits))

# If using an older version of Chilkat, the key size can be obtained like this:
xml = chilkat2.Xml()
xml.LoadXml(pubKey.GetXml())

binDat = chilkat2.BinData()
binDat.AppendEncoded(xml.GetChildContent("Modulus"),"base64")

numBits = 8 * binDat.NumBytes
print("Number of bits = " + str(numBits))